NASA’s Rover Finds Evidence That Changes What Scientists Thought About Water on Mars
.jpg "LAKE BUENA VISTA , FL - APRIL 6: In this handout image provided by Walt Disney World Resort, a simulated Mars Rover makes tracks through red soil at Walt Disney World Resort April 6, 2004 in Lake Buena Vista, Florida.")
NASA’s Curiosity rover has discovered tiny mineral nodules on Mars that suggest groundwater persisted on the planet much longer than previously believed, expanding the window during which microbial life could theoretically have existed.
The rover has spent roughly six months exploring unusual geological formations on Mars known as boxwork — crisscrossing ridges that resemble giant spiderwebs stretching across the surface for miles when viewed from orbit.
Detailed images captured up close by the rover are now revealing bumpy, pea-sized nodules clinging to those ridges and nestled in the hollows between them.
Scientists say these tiny structures point to groundwater activity that lasted far longer than anyone previously thought.
The boxwork formations consist of low ridges about 3–6 feet tall with sandy hollows between them, creating a web-like pattern visible from space.
“These ridges are maybe two parking spaces wide, and they stand 3 to 6 feet tall above the sandy hollows between them. So would be a pretty fun landscape to ride your BMX bike across,” said Tina Seeger of Rice University in Houston, one of the mission scientists leading the boxwork investigation, in an interview with NewsNation.
Scientists believe the formations took shape over an immense span of time through a multi-step process.
Groundwater once flowed through fractures in bedrock beneath the Martian surface, depositing minerals that strengthened certain areas of rock. Relentless wind erosion then stripped away weaker surrounding rock, leaving the reinforced areas as raised ridges.
Before Curiosity reached the boxwork region, scientists only had orbital images of the formations. Their exact structure and composition remained uncertain.
The rover’s detailed images and samples revealed something unexpected: bumpy, egg-like nodules scattered across the terrain, formed from minerals left behind as groundwater dried out billions of years ago.
Why Water Matters for Life on Mars
The formations are located on Mount Sharp, a mountain about 3 miles tall that Curiosity has been ascending. Each layer represents a different period in Mars’ climate history, making it a natural archive of the planet’s past.
As the rover climbs higher, the environment shows signs that water gradually disappeared over time, though occasional periods of returning rivers and lakes occurred. Finding boxwork so high up the mountain was a significant surprise.
“Seeing boxwork this far up the mountain suggests the groundwater table had to be pretty high,” Seeger said. “And that means the water needed for sustaining life could have lasted much longer than we thought looking from orbit.”
Water is considered a fundamental requirement for life as we understand it. If groundwater persisted on Mars longer than previously believed, it expands the window during which microbial life could theoretically have taken hold beneath the planet’s surface.
“We all need water. All sorts of microbes need water. So our investigation on Mars has been about looking for signs that there was water and signs that it was a neutral pH, a good temperature, where microbes could have lived,” Seeger said.
“So, now that we see this evidence for later-stage groundwater where we could have maybe had microbes living in the subsurface, if they were there, we can keep looking for fossil evidence,” she added.
Strange Nodules Found in Unexpected Places
Beyond the ridges, Curiosity also found small mineral nodules that have puzzled scientists.
The nodules are typically signs of ancient groundwater activity, which was expected.
What surprised researchers was where they turned up — not near fractures, where scientists would normally expect them, but along ridge walls and inside the hollows between ridges.
Scientists do not yet fully understand why the nodules appeared in these unexpected locations.
One possible explanation is that the ridges may have been cemented by minerals first, and later groundwater activity could have then created nodules around them. That hypothesis has not been confirmed, and the investigation continues.
Navigating a Rocky Obstacle Course
Getting close enough to study the formations has been no easy feat. The ridges are barely wider than Curiosity itself, and the rover weighs 899 kilograms — nearly one ton.
Rover drivers must guide it across ridge tops and then down into sandy hollows. Wheels can slip in sand, and turning in narrow spaces is a constant challenge.
“It almost feels like a highway we can drive on. But then we have to go down into the hollows, where you need to be mindful of Curiosity’s wheels slipping or having trouble turning in the sand,” said operations systems engineer Ashley Stroupe of NASA’s Jet Propulsion Laboratory in Southern California, which built Curiosity and leads the mission.
“There’s always a solution. It just takes trying different paths,” Stroupe added.
What Comes Next
NASA released Curiosity’s first boxwork photos in June 2025, shortly after the rover reached the rocky ridges.
On Monday, Feb. 23, the agency released two more images showing the structures in much greater detail, giving scientists a closer look at the textures and egg-like nodules that have sparked so much scientific interest.
The rover is expected to leave the boxwork behind in March, continuing its climb up Mount Sharp. Each new layer of the mountain promises to reveal another chapter in Mars’ climate history.
The boxwork investigation has already reshaped scientists’ understanding of how long water — and the possibility of life — may have lingered on Mars.
The crisscrossing ridges and their tiny, mineral-rich nodules tell a story of a planet once far wetter than its dusty surface suggests today.
BOTTOM LINE: Curiosity is expected to leave the boxwork region in March and continue climbing Mount Sharp, where each new geological layer could yield more evidence about whether Mars once had conditions capable of supporting life.
Production of this article included the use of AI. It was reviewed and edited by a team of content specialists.
